Tobmod beinebt i oblaud



UNITED STATES PATENT OFFICE.

TORMOD REINEB'IFGBLAND, 0F HAUGESUND, NORWAY.

EXTRACTION 0F MOLYIBDENUM.

No Drawing.

To all whom it may concern:

Be it known that I, ToRMon REINERT Fon- LAND, a subject of the King of Norway, residing at Haugesund, in the Kingdom of Norway, have invented certain new and useful Improvements in the Extraction of Molybdenum; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to the extraction of metallic molybdenum and has for its object a process 'by means of which metallic molybdenum free from carbon could be obtained.

The processes which are at present in use for the manufacture of molybdenum metal are based upon a reduction operation whereby the metal is obtained as an alloy viz. ferromolybdenum. This is brought about in an electric furnace in which the sulfid or oxid of molybdenum is treated. This known process is connected with several drawbacks. Thus a comparatively large loss of molybdenum takes place owing to the fact that during the-reactions taking place in the furnace molybdenum trioxid is produced, which compound is volatile at the high temperatures necessary for the reduction. Further the. high temperatures give rise to the formation of carbid so that a product containing a greater or less percentage of carbon will result. This content of carbon involves a reduction of the commercial value of the product. I

According to the present. invention metallic. molybdenum free from carbon is produced from molybdenum chlorid by an electrolytic reduction process at comparatively low temperatures.

It has been found that chlorid of molybdenum is a non-conductor of electricity so that the electrolytic decomposition of pure chlorid of mol bdenum in a molten condition is impracticable. It has been suggested therefore to effect decomposition of molybdenum chlorid as a secondary process in {the presence of chlorid of sodium. This process,

Specification of Letters Patent.

Patented June 3, 1919.

Application filed April 5, 1918. Serial No. 226,934.

however, has the drawback that considerable quantities of molybdenum chlorid escape in' tures of'below 200 C. When such a mix-- ture is subjected to electrolysis metallic molybdenum separates out at. the cathode. In this'instance the reaction may be considered as a result of the electrolytic decomposition of aluminium chlorid into chlorin and metallic aluminium, which latter reacts with the chlorid of molybdenum forming metallic molybdenum and chlorid of alu- I'ninium.

For the purpose of carrying the electrolysis into effect I have employed a furnace of the U-tube system but it is apparent that also other furnaces suitable for the electrolysis of fused salts may be em loyed. The process may be carried into effect with any other chlorids than those above referred to provided that the element to which the chlorin is combined has a greater affinity to chlorin than the molybdenum.

I claim:

The process of producing molybdenum metal from molybdenum chlorid which consists in electrolyzing a fused salt mixture comprising chlorids of molybdenum,sodium and aluminium.

In testimony that I claim the foregoing as my invention, I have signed my name in presence of two subscribing witnesses.

TOR-MOD REINERT FoRLAND.

Witnesses:

HENRY C. A. DAMM, M. RISER. 

